The Tour du Mont Blanc or TMB is one of the most popular long-distance walks in Europe. It circles the Mont Blanc massif, covering a distance of roughly 170 kilometres (110 mi) with 10 kilometres (6.2 mi) of ascent/descent and passes through parts of Switzerland, Italy and France.
It is considered one of the classic long-distance hiking trails. The circular route is normally walked in an anti-clockwise direction in 11 days. It is also the route of an annual mountain marathon in which the winner normally covers the entire distance in less than 24 hours. Usual start points are Les Houches in the Chamonix valley or Les Contamines in the Montjoie valley (in France), Courmayeur from the Italian side, and either Champex or a point near Martigny in Switzerland. The route passes through seven valleys around the Mont-Blanc massif, an anti-clockwise start in Chamonix would lead through the Chamonix (or Arve) valley, then Montjoie, Vallee des Glaciers, Italian Val Veni, Val Ferret, Swiss Val Ferret, and either the Arpette or Trient valley in Switzerland, dependent on the route chosen.
The ‘official’ route has changed over the course of the years and many alternatives, or ‘Variantes’, exist to the standard route. Some of these take the intrepid walker onto paths requiring greater fitness, awareness and skill. Others provide less demanding options, which are often quicker than the accepted route, but provide lesser viewpoints onto the mountain ranges. For a part of the way, between the summit of Brevent and the Col de la Croix du Bonhomme, the route coincides with the European long-distance footpath GR5 as it makes its way from the North Sea to the Mediterranean Sea. A link can also be made with the walkers' Haute Route from Chamonix to Zermatt in the Swiss Alps.